Exhibit 5.1

Ladies and Gentlemen:

We have acted as counsel to 3M Company, a Delaware corporation (the “Company”), in connection with the Company’s offering of $550,000,000 aggregate principal amount of its 4.800% notes due 2030 and $550,000,000 aggregate principal amount of its 5.150% notes due 2035 (the “Notes”) in an underwritten public offering pursuant to an underwriting agreement dated March 4, 2025 (the “Underwriting Agreement”) among the Company and BofA Securities, Inc., Citigroup Global Markets Inc., Deutsche Bank Securities Inc. and J.P. Morgan Securities LLC, as representatives of the several underwriters listed in Schedule I thereto (the “Underwriters”). The Notes are to be issued pursuant to an Indenture dated November 17, 2000 (the “Base Indenture”) between the Company and The Bank of New York Mellon Trust Company, N.A. (formerly known as The Bank of New York Trust Company, N.A. and as successor to Citibank, N.A.), as trustee (the “Trustee”), as supplemented by the First Supplemental Indenture dated July 29, 2011 (the “First Supplemental Indenture” and, together with the Base Indenture, the “Indenture”). The Company has filed with the Securities and Exchange Commission a Registration Statement on Form S-3 (File No. 333-269639) (the “Registration Statement”) pursuant to the provisions of the Securities Act of 1933, as amended (the “Securities Act”) for the purpose of registering the offer and initial sale of certain securities, including the Notes.

We, as your counsel, have examined and have relied as to matters of fact upon originals or copies of such corporate and other records, agreements, documents and other instruments and certificates or comparable documents of public officials and of officers and representatives of the Company and such other persons, and we have made such other investigations, as we have deemed necessary or advisable as a basis for the opinion expressed below.

In rendering the opinion expressed herein, we have, without independent inquiry or investigation, assumed that (i) all documents submitted to us as originals are authentic and complete, (ii) all documents submitted to us as copies conform to authentic, complete originals, (iii) all documents filed with or submitted to the Commission via the Electronic Data Gathering, Analysis and Retrieval system (“EDGAR”), except for required EDGAR formatting changes, conform to the versions of such documents reviewed by us prior to such formatting, (iv) all signatures on all documents that we reviewed are genuine, (v) all natural persons executing documents had and have the legal capacity to do so, (vi) all statements in certificates of public officials and officers of the Company that we reviewed were and are accurate, (vii) all representations made by the Company as to matters of fact in the documents that we reviewed were and are accurate and (viii) each party to the global notes representing the Notes and the Indenture (collectively, the “Documents”) has satisfied those requirements that are applicable to it to the extent necessary to make such document a valid and binding obligation of such party, enforceable against such party in accordance with its terms, except that we make no such assumption to the extent we have specifically opined as to such matters with respect to the Company.

Based upon and subject to the foregoing, and subject also to the assumptions and qualifications set forth below, and having considered such questions of law as we have deemed relevant and necessary as a basis for our opinion, we are of the opinion that, the Notes have been duly authorized by the Company in accordance with the Indenture and, when executed and authenticated in accordance with the provisions of the Indenture and delivered to, and paid for by, the Underwriters in accordance with the terms of the Underwriting Agreement, the Notes will constitute valid and legally binding obligations of the Company, enforceable against the Company in accordance with their terms and entitled to the benefits of the Indenture.

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Our opinion expressed above is subject to (1) bankruptcy, insolvency, reorganization, moratorium or other similar laws relating to or affecting the rights of creditors generally and (2) the application of general principles of equity (regardless of whether considered in a proceeding in equity or at law), including without limitation concepts of materiality, reasonableness, good faith and fair dealing. We express no opinion as to (i) the enforceability of any waiver of rights under any usury or stay law or (ii) the validity, legally binding effect or enforceability of any provision providing for liquidated damages, default interest or permitting holders to collect any portion of stated principal amount upon acceleration to the extent determined to constitute unearned interest.

We have also assumed that the execution, delivery and performance by each party to each Document to which it is a party (a) are within its corporate powers, (b) do not contravene, or constitute a default under, the certificate of incorporation or bylaws or other constitutive documents of such party, (c) require no action by or in respect of, or filing with, any governmental body, agency or official and (d) do not contravene, or constitute a default under, any provision of applicable law or regulation or any judgment, injunction, order or decree or any agreement or other instrument binding upon such party, provided that we make no such assumption to the extent that we have specifically opined as to such matters with respect to the Company.

We are members of the Bar of the State of New York and the foregoing opinion is limited to the laws of the State of New York, except that we express no opinion as to any law, rule or regulation that is applicable to the Company, the Documents or such transactions solely because such law, rule or regulation is part of a regulatory regime applicable to any party to any of the Documents or any of its affiliates due to the specific assets or business of such party or such affiliate.

We hereby consent to the filing of this opinion as an exhibit to a Current Report on Form 8-K to be filed by the Company on the date hereof and further consent to the reference to our name under the caption “Legal Matters” in the related prospectus supplement, which is part of the Registration Statement. In giving this consent, we do not admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act.